The Relevance of Irrelevance: Explanation in Systems Biology

Abstract

In this chapter I investigate explanations in systems biology that rely on dynamical models of biological systems. I argue that accounts of mechanistic explanation cannot easily make sense of certain features of dynamical patterns if they restrict themselves to change-relating relationships. When investigating the use of such models, one has to distinguish between the concepts of causal or constitutive relevance on the one hand, and explanatorily relevant information on the other. I show that an important explanatory function of mathematical models consists in elucidating relationships of non-dependence. Notably, the fundamental concept of robustness can often be accounted for in this way, and not by invoking separate mechanistic features. Drawing on examples from the scientific literature, I suggest that an important aspect of explaining the behavior of a biological mechanism consists in elucidating how in the systemic context components are not, or only weakly, dependent on each other.